<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <script lang="javascript">
    function myNew(Func,...args){
      const obj = {}
      obj.__proto__=Func.prototype;
      let result = Func.apply(obj,args);
      return result instanceof Object ?result:obj;
    }
    function Person(name,age){
      this.name = name;
      this.age = age;
    }
    Person.prototype.say = function () {
        console.log(this.name)
    }

    let p = myNew(Person,'huihui',123);
    console.log(p);
    p.say()
  </script>
</body>
</html>